Chinchilla., page-14

I doubt there is any high temps in the UCG process, the process is designed to burn inefficiently to produce more gasses. The geology wont be affected by high temps anyway, more likely subsidence if the strata is fragile and this leads to cracking to the surface, but you wouldn't expect any subsidence from 200m down even if the ground was unstable and fragile. It would nearly have to be soup to get any movement on the surface.

It would be very easy to ensure that the cover over any UCG ignition would be stable with no seepage of gas from diamond drilling and core assessment. If there actually is gas coming from the trial area you would have to expect that the fire is not out for sure and LNC have completely botches the geology assessment of the cover, and have possibly left some drill holes open to the ignition point acting as a draw point for oxygen.
Even that is very suspect so where is the fire getting its oxygen from to keep the chemical reaction for fire going? Seems unlikely unless there is an oxygen source from somewhere. And underground you would expect any available oxygen to be used up very quickly, ie try breathing while floating around in rock.

Its hard to get any real information from these articles as looneys from anti and pro everything stick their nose in and the information turns to sheet. Same as politics I suppose.

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